All - this might be an opportunity for me to expand on unsound’s response to dmac67 regarding the ’improved’ CS3.6s. Indeed Jim’s approach to design was to specifically control any system misbehavior in pursuit of absolute fidelity to the input signal. In the case of drivers and their crossovers, all those parallel XO circuits serve to correct and control any anomalies and resonances so the drivers can span their 7 to 8 octaves in net 6dB/octave atentuation as required for true phase-coherent response. Additionally he sought for an absolutely neutral tonal balance (as he interpreted the term). So, any change in any driver would require reciprocal crossover changes to keep the outputs loyal to his design intentions.
Let’s unpack the "Rosewood 3.6 offering".
"Rosewood" as used by Thiel is the wood of commerce in the Dalbergia genus, specifically Dalbergia nigra, Brazilian Rosewood, considered the most classic and valuable of the lot. The offered speakers are what Thiel called Morado, which is the lowland Bolivian variety of the genus Machaereum (Amberwood being the upland variety.) It’s a beautiful wood, many people refer to it as a ’near Rosewood’, etc. but it is not the upcharged wood that Thiel calls Rosewood.
The "rebuilt crossovers" is of interest to me. It would be of great interest to learn what was done to those crossovers to compensate for the different midrange and modified tweeter. Seriously, if a schematic could be gotten, I’d love to see it. In Thiel-land the final months of critical listening would be spent fine-tuning the XO to prune performance of the specific drivers in their cabinet toward the design goals. These drivers are different.
The ’original tweeter, but with soft domes’ are "better sounding" than Thiel’s aluminum domes.That is a matter of opinion and will be true for some listeners. However, the differences in the soft diaphragm will include mass, compliance, breakup and resonance behaviors. If the seller compensated for those differences, I’d love to hear and study that work. If not, the output will vary from the design intent. A historical note re that tweeter. It was developed for the CS5 and trickled down to the 2.2 and 3.6. It was a massive joint undertaking between Thiel and Berger, the lead development engineer at Vifa. It incorporates the underhung motor and copper shunts that became Thiel trademarks. Copper shunts for the voice coil and pole piece were not in use in the late 80s when Jim discovered their efficacy through Finite Element Analysis. We investigated patenting the solution to learn that Faraday had discovered it, and it was in the public domain, although not in use for loudspeakers at that time. Note that other manufacturers call their rings "Faraday Rings", but Jim is who introduced them to audio.
Let’s look at the soft vs aluminum dome issue in terms of our relationship with Vifa, our long-term development partner until we outgrew their tolerance for our eccentric requirements. We co-developed many drivers with them from about 1980 to the late 1990s when we gradually took driver manufacture in house; not because we wanted the extra work of making drivers, but because our solutions were too difficult, expensive and niche for them. With this UltraTweeter as an example, we co-developed drivers with Vifa who retained rights to sell them (and all our joint drivers) to any and all their customers; how they amortized their tooling and development costs. Berger implemented and sampled Jim’s aluminum dome and simultaneously the soft dome for a broader customer base. Both are in the same structure so that the Thiele/Small parameters will be very similar. But the soft dome will have individual variation far exceeding the aluminum. That’s the principal reason Jim chose aluminum, so that his optimized crossover could apply to all drivers, rather than some lesser percentage using any soft diaphragm with their greater divergence from the norm. That story goes on and on, but I’ll take pity in this late hour. Either UltraTweeter will sound "good", but the aluminum one will consistently produce the designer’s intention.
The midrange gets far sticker because the chosen replacement uses a different motor and cone. It may very well be an excellent driver, but the 10mm voice coil length suggests a normal overhung motor, plus most all the Thiele/Small parameters also change. So an XO redesign would be required to achieve Jim’s level of accuracy. Again, I’d love to see the XO schematic to see what this designer has done.
The woofer remains stock.They are bullet-proof and rarely fail. I wonder what XO upgrades, if any, the seller applied there.
None of what I have written here is to disparage the seller or the potential care and expertise applied. However, I do point out the large undertaking, fraught with pitfalls in arriving at a speaker similar to Jim’s product. I suspect that every person on this thread would pick it blind as being a different speaker from the original CS3.6.
Mac - thanks for this opportunity to expound on what makes a Thiel a Thiel. If you choose to get this pair, I would love to work with you to document their particulars as they relate to my growing stable of upgrade ideas and directions for classic Thiel models.
Cheers,Tom
